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Use the Gauss-Jordan method to solve the following system of equations x+y 7 3x+2y= 17 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. The solution is (Туре an ordered pair.) O B. There are infinitely many solutions. The solution is y, where y is any real number (Use integers or fractions for any numbers in the expression.) O C. The system is inconsistent

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Answer:

The system
x+y=7\\3x+2y=17 has a unique solution
x=3\\y=4

Explanation:

We have the system of equations:


x+y=7\\3x+2y=17

To solve this system for Gauss-Jordan method we need the augmented matrix, which is:


\left[\begin{array}c1&1&7\\3&2&17\end{array}\right]

Next we need to transform the augmented matrix to the reduced row echelon form via elementary row operations as follows:

  • Row Operation 1: add -3 times the 1st row to the 2nd row


\left[\begin{array}cc1&1&7\\0&-1&-4\end{array}\right]

  • Row Operation 2: multiply the 2nd row by -1


\left[\begin{array}cc1&1&7\\0&1&4\end{array}\right]

  • Row Operation 3: add -1 times the 2nd row to the 1st row


\left[\begin{array}cc1&0&3\\0&1&4\end{array}\right]

From the reduced row echelon form we have the solution of the system


x=3\\y=4

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